This invention relates to a method of creating animated video images.
Traditionally, animation has been achieved by displaying multiple images in rapid succession, with the objects in each frame being displaced by a small amount from the objects in the previous frame. When viewed by the human eye, this rapid succession of images is perceived as movement of the objects. When the frame rate is sufficiently high, and the displacement of objects from one frame to another is small,enough, the movement appears to be smooth.
Originally, animation was a very painstaking process in which every frame of the moving image was drawn by hand. More recently, computers have been used to generate the images required to create the appearance of smooth motion. Computerized animation was a major advance over hand-drawn animation, because it eliminated a large portion of the time and labor previously required to produce animation.
Even so, animation remains expensive to implement, because it still requires significant amounts of labor and computer resources.
One existing technique that overcomes these disadvantages, to some extent, is the SQUIGGLEVISION.TM. simulated animation technique. (SQUIGGLEVISION is a trademark of Tom Snyder Productions, Inc.). With SQUIGGLEVISION.TM. simulated animation, the edges of objects in the image are squiggled to create an electric-line look instead of actually moving the objects.
The existing method of creating SQUIGGLEVISION.TM. simulated animation is a manual process: An artist creates a still image and it is manually traced four times, resulting in a total of five very similar versions of the same image. While these five versions are quite similar, there are, in fact, slight random differences between each of the five images as a result of the manual tracing process. Each of the five images is then pasted on to identical copies of a background image. Then, these five images are displayed sequentially in successive video frames in a repeating sequence.
Because of the slight differences between the five images, the edges and features of the character look like they are boiling or squiggling when the sequentially displayed images are viewed by the human eye. The random nature of the inter-image variations introduced by the manual tracing enhances the squiggling effect.
The result is a reduced cost simulation of animation. This technique also advantageously creates the illusion that the characters are three dimensional because different parts of the background, at the edges of the character, are uncovered in the different frames.
The existing manual SQUIGGLEVISION.TM. simulated animation technique can also be used in conjunction with animation of a character's mouth when a character is talking. The mouth is traced in five different positions which are then displayed in sequence to create the impression that a character is talking.
While this method of producing simulated animation requires far less labor than traditional animation, the tracing and pasting process still requires a significant amount of manual labor. For example, a typical half hour program could contain over 200 still images that must be squiggled. With the manual tracing method described above, 800 manual tracing operations would be required to squiggle all 200 images.
Eliminating this manual step would reduce the cost of the process significantly, and cut the time needed to prepare a program.
Until now, however, efforts to create a simulated animation effect automatically using a computer have been unsuccessful, because random inter-image variations that enhance the squiggling effect are difficult to generate by computer.